Do you remember exactly where you were and what you were doing when you heard the news that President John F. Kennedy was shot? Or when the space shuttle Challenger exploded? Or when the 9/11 terrorist attacks occurred? If so, that's a flashbulb memory. When something traumatic occurs, our brains can sometimes create a very sharp memory of the event that includes minute details, much like a photograph. This is because such events are both personal — we experience them either firsthand or via TV — and public — everyone around us does, too, and subsequently talks about them [source: Law].

The concept of flashbulb memories was first proposed by two psychologists in 1977, and it's still controversial. The naysayers argue that studies show people's flashbulb memories do deteriorate over time, and sometimes significantly. But flashbulb backers say those studies don't compare the amount a flashbulb memory deteriorates over time compared to a regular one. Other studies show flashbulb memories really aren't that sharp over time, but we perceive them as quite vivid, likely because of their strong emotional component. What does seem accurate, though, is that the closer and more emotionally invested you are to a traumatic event, the better your recollection of it [source: Law].